• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.337-338
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• 2012

As a rahmen structure, the connection among columns of Green frame is divided into three types such as sleeve, coupler (column pre and post installation), and bolt. The bolt type consists of six types according to steel frame shape and each type has different constructability, safety, structural performance, cost, and quality. Therefore, the analysis of comparison among the types is necessary. The objective of this study is to analyze the characteristics according to the shape of six bolt types to select the appropriate connection of Green frame. The results of this study can be used as a basic study for indentifying the characteristics of steel frame on site applying bolt type connection of Green frame. In addition, this study can be applicable to compare and analyze the performance and constructability of six bolt types in detail.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.483-491
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• 1997

The purpose of this study id to define the behavior of the girder ledge of precast girder-beam joint in Frame Type Precast Concrete Construction Method. And in behavior, girder ledge is different with bracket, because of longitudinal effective width and longitudinal bending. specif c objectives of this study are followed: $\circled1$ To investigate the effects of concrete compressive strength on the maximum shear strength of girder ledge, $\circled2$ To investigate the effects of the shear-span ratio and effective area on behavior of girder ledge, $\circled3$ To investigate the effects of the types of reinforcement on behavior and maximum shear strength of girder ledge, $\circled4$ To study the applicable possibility of the suggested shear friction formulas to estimating the shear strength of girder ledge.

• International Journal of High-Rise Buildings
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• v.4 no.3
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• pp.181-189
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• 2015

Shimizu Corporation Tokyo Headquarters, one of the city's leading office buildings, features many pioneering technologies that contribute to a sustainable society through environmental stewardship and a sophisticated disaster management facility. In terms of structural engineering, a seismic isolation system incorporating reinforced concrete core walls and precast concrete perimeter frames create a robust structure in the event of a large earthquake. In addition to the seismic resistance of the structure, several pioneering construction methods and materials are adopted. This office building can serve as a basis for new design and construction approaches and methodologies to ensure safe and economical structures.

• KCI Concrete Journal
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• v.11 no.3
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• pp.191-199
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• 1999

A Precast frame system with hybrid beam-column connections was proposed in this study. An analytical study evaluated the system under seismic loadings. Four buildings with different heights were modeled in which each building had three types of joint details (A. B, C). Thus, twelve buildings were examined with variables such as building height and joint detail. Four earthquake records were applied to the buildings as input ground motions. All the records were normalized to the intensity of 0.25g to assess behavior under the same intensity of seismic excitation. All the joint types showed almost identical results except for the Mexico earthquake which was scaled up from 0. 1g to 0.25g. Buildings with the type C joint exhibited the largest deflection for the Mexico earthquake. It was concluded that type B joint could be used in a high seismic zone and the type C joint could possibly be used in the regions of low to medium seismic activity.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.41-42
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• 2022

This study analyzed the process related to the linkage between on-site work targeting the middle size Precast Concrete(PC) public apartment building with beam-column system and prepared on-site works flow relationship diagram in which the wet process consists of core Critical Path(CP) to prepare a network diagram of the Precedence Diagram Method(PDM). Through this study, it is expected that it will be possible to maximize the project management capability by suggesting a method to minimize risk factors and the optimized process management of the beam-column system PC public apartment building.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.10
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• pp.3-10
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• 2018

Hybrid Prestressed Precast Concrete System (HPPC system) is a newly developed frame system that can improve the performance of precast concrete (PC) joints by post-tensioning. In particular, the details proposed in this study can reduce the lifting weight of the PC members and eliminate problems caused by cracks in the joints that occur under service loads. This study performed an evaluation on the negative moment performance of full-scaled HPPC girders. The test specimens were cast with or without slabs, with bonded or unbonded tendons, and had different post-tensioned lengths in tensile section. The test results showed that the specimens with slabs had significantly higher stiffness and strength than those without slabs. There were no differences in the flexural behavior between those with bonded or unbonded tendons, and between those with short or long post-tensioned lengths in the negative moment region.

• Steel and Composite Structures
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• v.29 no.5
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• pp.603-622
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• 2018

Precast concrete structures are erected from individual prefabricated components, which are assembled on-site using different types of connections. In the present design of these structures, beam-to-column connections are assumed pin jointed. Bolted billet beam to-column connections have been used in the precast concrete industry for many years. They have many advantages over other jointing methods in component production, quality control, transportation and assembly. However, there is currently limited information concerning their detailed structural behaviour under vertical loadings. The experimental work has involved the determination of moment-relative rotation relationships for semi-rigid precast concrete connections in full-scale connection tests. The study reported in this paper was undertaken to clarify the behaviour of such connections under symmetrical vertical loadings. A series of full-scale tests was performed on sample column for which the column geometry and bolt arrangements conformed to successful commercial practice. Proprietary hollow core floor slabs were tied to the beams by 2T25 tensile reinforcing bars, which also provide the in-plane continuity across the connections. The contribution of the floor strength and stiffness to the flexural capacity of the joint is currently neglected in the design process for precast concrete frames. The flexural strength of the connections in the double-sided tests was at least 0.93 times the predicted moment of resistance of the composite beam and slab. The secant stiffness of the connections ranged from 0.94 to 1.94 times the flexural stiffness of the attached beam. In general, the double-sided connections were found to be more suited to a semi-rigid design approach than the single sided ones. The behaviour of double sided bolted billet connection test results are presented in this paper. The behaviour of single sided bolted billet connection test results is the subject of another paper.

• Journal of the Korea Concrete Institute
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• v.27 no.4
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• pp.451-458
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• 2015

The infill-wall strengthening method has been widely used for the seismic performance enhancement of the conventional reinforced concrete (RC) frame structures with non-seismic detail, which is one of the promising techniques to secure the high resisting capacity against lateral forces induced by earthquake. During the application of the infill-wall strengthening method, however, it often restricts the use of the structure. In addition, it is difficult to cast the connection part between the wall and the frame, and also difficult to ensure the shear resistance performances along the connection. In this study, an advanced strengthening method using the externally-anchored precast wall-panel (EPCW) was proposed to overcome the disadvantages of the conventional infill-wall strengthening method. The one-third scaled four RC frame specimens were fabricated, and the cyclic loading tests were conducted to verify the EPCW strengthening method. The test results showed that the strength, lateral stiffness, energy dissipation capacity of the RC frame structures strengthened by the proposed EPCW method were significantly improved compared to the control test specimen.

• Journal of the Korean housing association
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• v.26 no.2
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• pp.103-110
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• 2015

Precast Concrete (PC) construction method can be the one that is suitable for long-life housing due to its merit in respect of maintenance and durability based on crack-free from mass production with indirect construction cost-saving-effect due to shortening construction period comparing to the conventional construction method, but it has the problem that causes the raise of direction construction costs. So, this study analyzed its economic feasibility of PC method whose maintenance and durability are excellent for underground parking lot of apartment house for accomplishing cost-saving long-life housing by applying the various structural system. In evaluation of unit module structural system, two-way PC system requires 10 to 28% more costs for frame work than RC rigid frames, and, one-way PC system 98~112%. Although it varies depending on the method, the costs are similar to RC rigid frame structure, provided a proper method is adopted. Also, Model 11, which was most economical in the evaluation, was applied to an real parking lot and about 2 to 6% of construction costs was reduced than RC rigid frames. This seems to be because, although PC system has a higher production cost, introduction of P.S (prestress) reduces member depth and, therefore, height, as well as the number of members per unit module.

• Journal of the Korea Institute of Building Construction
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• v.24 no.4
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• pp.495-506
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• 2024

Unlike reinforced concrete(RC) construction, the primary determinant of construction schedule for precast concrete(PC) apartment buildings is the lifting equipment. To establish a dry process-centric construction schedule, this study analyzes the lifting unit process for core, internal, and external PC wall components, which differ from traditional PC components. By examining the assembly process of these wall types, the study aims to determine the construction cycle for a standard floor frame of a PC apartment building. The findings will serve as foundational data for developing construction schedules for PC apartment buildings utilizing PC walls.